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<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        let arr=[{name:'Jazz'}, {name:'Blues'}]
       arr.map(itm=>{
            itm.age={}
            return itm
        })
        console.log(arr);
    </script>
</body>

</html>